When New York department store magnate Cyrus Embrich is found stabbed to death at his office desk, the police have little evidence to go on. Embrich's secretary reveals that her employer had been in fear of his life, and in the event of anything happening to him, he had asked her to call in the famed private investigator 'Probability' Jones to assist the police. Aided - and at times led - by his able assistant Rosanna Beach, Jones finds himself caught up in the most complex and dangerous case of his career ...